fn main() {
    another_function(5);

    println!("3 + 4 =  {}", sum(3, 4));
}

// 函数
fn another_function(x: i32) {
    println!("The value of x is: {}", x);
}

// 带返回值的函数
fn sum(x: i32, y: i32) -> i32 {
    return x + y;
}
